Therapeutic Drug Monitoring (TDM) in Child & Adolescent Psychiatry

We aim to analyse in adolescents with mental illness effectiveness, side effects, and serum level concentrations of antipsychotics (olanzapine and aripiprazole), antidepressants (Duloxetine, Atomoxetine) by means of "Therapeutic Drug Monitoring" (TDM) in order to optimize dosage - effect relations and minimize unwanted side effects.

Therapeutic drug monitoring is becoming a quality measure in psychopharmacotherapy in adults and children and has been used successfully recently (Hiemke 2008). In 2007, the German Child & Adolescent Psychiatry University Clinics have founded a network the "TDM-network" headed by Profs. C. Mehler-Wex and J. Fegert in Ulm (www.tdm-kjp-de). The Viennese Child and Adolescent Clinic is part of this network. Most importantly, this network must and wants to be independent from the pharmaceutical industry in order to get un-biased scientific results and data. Within this network, which has been successfully established in the participating clinical departments it is possible to take the lead in several scientific areas.

Highest ethical standards, data-protection and rigorous designs are needed to protect childrens' and adolescents' rights.

Therapeutic drug monitoring (TDM) and its implication for treatment and research: By definition, TDM signifies the dosage of a drug by controlling its concentration in serum. It aims at establishing the therapeutical range of the drug given and thus at minimizing the risk of over- or undermedication (Pschyrembel 2002). Indications for therapeutic drug monitoring in general comprise the following aspects: - Poor response to the administered drug despite a clinically established dosage - Severe side effects despite a clinically established dosage - Combining medications which bear potential to interact adversely with each other - Treatment of patients at risk (immunosuppression, patients in intensive care, patients at need of longterm treatment, patients with a high level of comorbidity or genetic abberations, patients at risk of non-compliance)- Questionable adherence to the treatment regime -Child and adolescent populations

The scientific background of TDM refers to the assumption that the serum concentration of substances along with their active metabolites represent a better measure of their concentration in the brain as the actual dose (Laux & Riederer, 1992; Baumann et al., 2004). Additionally, it is stated that there is a defined relation between serum concentration and clinical effect. This correlation could be confirmed e.g. for the tricyclic antidepressants imipramine und desipramine (Baumann et al., 2004).